Molded pulp articles



p 17, 1963 R. F. REIFERS 4 3,104,044

MOLDED PULP ARTICLES 1 Filed June 19, 1961 lob . Lglllllllllllp 4 I Jr:4-1 ll-m Richard E Reifers BY m. (/0. FC N ATTORNEY United States PatentIce 3,104,044 MOLDED PULP ARTICLES Richard F. Reifers, New Canaan, Conn,assignor to Diamond National Corporation, New York, N.Y., a corporationof Delaware Filed June 19, 1961, Ser. No. 118,187 2 Claims. (Cl.229-2.5)

The present invention relates :to molded pulp articles, and moreparticularly to molded pulp containers which have relatively high sidewalls with slots therein.

This application is a continuation-in-part of applicants copendingapplication Serial No. 38,354, filed June 23, 1960, now Patent No.3,075,872.

Molded pulp containers which are relatively deep and have a plurality ofslots in the side walls have heretofore presented several problems.First of all, the slots in theside walls have resulted in a loss ofrigidity and strength inthe side walls. Further, it is necessary thatsuch containers be nested during storage and shipment. Due to the highside walls with the resulting friction it has been round difficult toseparate the nested containers one from another without damaging them.

It is therefore an object of the present invention to provide a moldedpulp container suitable for the packaging of innit and vegetables whichhas ventilating slots in the side walls and yet has the necessaryrigidity and strength.

It is a further object of the present invention to provide a molded pulpcontainer with relatively high side walls which can be nested within oneanother and can be subsequently withdrawn therefrom without damage tothe container.

Other objects and the nature and advantages of the instant inventionwill be apparent from the following description taken in conjunctionwith the acompanying drawings, wherein:

FIG. 1 is a top plan view of a molded pulp container in accordance withthe present invention;

FIG. 2 is a cross-sectional View along the line 22 of FIG. 1;

FIG. 3 is a cross-sectional view along the line 3--3;

and

FIG. 4 is a side elevational view partly in section show ing a pluralityof containers in nested relationship.

Referring to (FIG. 1, there is shown a molded pulp container which issubstantially square in shape and which is provided with rounded corners12. The container is provided with rfour side walls 14, 16, 18 and 20,each of these side walls extending upwardly in a slightly outwardlyinclined direction, (from a fiat bottom wall 22. The juncture betweeneach of the side walls and the bottom wall is slightly rounded.

111 each of the side walls, at the junction of each side wall and thebottom wall are a plurality of slots 24. As shown in FIG. 1, three slots24 are provided in each side wall. Each of the slots 24 are positionedso that a portion thereof extends into the bottom wall and a por-v tionextends upwardly into the side wall. As shown the slots extend only aslight distance into the bottom wall but extend upwardly approximatelyone half of the height of the side wall.

Between each adjacent pair of slots 24 in the side wall 2 is a flutedrib 28 which extends from the bottom wall upwardly to a shoulder 30which extends around the entire upper periphery of the container. Asshown, with three slots 24 in a side wall, there are provided two flutedribs 28. The ribs give suflicient strength to the side walls even withthe long slots therein.

The pontion of the side walls from the shoulder 30 to the upper edge ofthe container 32 has an inward slope as shown at 34. This inward slopein the upper p01 tion of the side wall acts to permit nesting withoutfrictional engagement of the side walls so that adjacent containers inthe stack can be readily separated.

Such articles with reverse angles or negative drafts as at 34 cannot bemolded directly due to the difficulty of removing the article from aforming die having such a negative drarft. Containers oi this type canbe molded using the method of memory azfter iorming as described inapplicants copending parent application, Serial No. 38,354, filed June23, 1960, Patent No. 3,075,872.

This method provides for first molding the container in a mold with theupper side wall portion vertical. The

preform is transferred to a transfer die having the desired inwardsloping upper surfaces as shown at 34, and

suction is applied to lock the wet preform to the configuration of thetransfer die. The container is then blown ttrom the transter die withthe upper portion being dragged over the inwardly extending projectionsof the die. During the subsequent drying process, the article returns tothe shape it had assumed on the transfer die throwgh the memory of beingin that position.

When two or more of the containers 10 are nested as shown in FIG. 4, theupper edge 32 of each container engages the shoulder 30 of the containerabove while the corresponding side walls are maintained out ofi-rictional engagement. This spacing of the side walls prevents stickingtogether of the containers, and the contact between the upper edge andthe shoulder is merely a support contact where the only force exerted isthe force of gravity.

The container described herein is particularly suited for the packagingof [fruit such as berries where extremely good ventilation is required.

Although the container illustrated is shown as being generally square inshape, the invention is not limited to such shape since it may berectangular, oval or even round.

-It will be obvious to those skilled in the art that various changes maybe made without departing from the spirit 'of the invention andtherefore the invention is not limited to what is shown in the drawingsand described in the specification, but only as indicated in theappended claims.

What is claimed is:

1. A molded fibrous article having increased rigidity and strengthcomprising a substantially flat bottom wall, side walls extending in anupwardly and outwardly inclined direction from each side of the bottomwall then outwardly of said inclined direction to form a peripheralshoulder, then upwardly to form upper side Wall por- Patented Sept. 17,1963' References Cited in the file of this patent UNITED STATES PATENTSFreeland Sept. 23, 1924 Kennedy Feb. 5, 1929 Chaplin May 16, 1944 HatchMar. 20, 1956 Emery Nov. 26, 1957 Lapham June 2, 1959 FOREIGN PATENTSFrance ....5 Feb. 7, 1906 Australia May 7, 1959

1. A MOLDED FIBROUS ARTICLE HAVING INCREASED RIGIDITY AND STRENGTHCOMPRISING A SUBSTANTIALLY FLAT BOTTOM WALL, SIDE WALLS EXTENDING IN ANUPWARDLY AND OUTWARDLY INCLINED DIRECTION FROM EACH SIDE OF THE BOTTOMWALL THEN OUTWARDLY OF SAID INCLINED DIRECTION TO FORM A PERIPHERALSHOULDER, THEN UPWARDLY TO FORM UPPER SIDE WALL PORTIONS TERMINATING INAN UPPER EDGE DEFINING A CONTINUOUS BAND EXTENDING ABOUT THE UPPERPERIPHERY OF SAID ARTICLE, AT LEAST THREE SLOTS IN EACH SAID SIDE WALLSOF THE ARTICLE, EACH SAID SLOT EXTENDING PARTIALLY INTO THE BOTTOM WALLAND PARTIALLY INTO THE SIDE WALL, AND A FLUTED RIB LOCATED BETWEEN EACHPAIR OF SLOTS, SAID RIB EXTENDING FROM SAID BOTTOM WALL AND TERMINATINGAT THE TOP AT SAID SHOULDER, EACH OF SAID SLOTS BEING OF A LENGTH OF ATLEAST ABOUT ONE-HALF THE LENGTH OF SAID RIBS.